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javajava-timeopencsvdatetime-parsingjava.time.instant

Parsing Instant using OpenCsv


I am trying to parse Instant from a CSV using OpenCsv this way:

@CsvDate("yyyy-MM-dd hh:mm:ss")
@CsvBindByName(column = "date")
private Instant date;

I know that OpenCsv is supposed to support java.time.

But when trying to use it I am getting the following exception:

Error parsing CSV line: 8.

...

Caused by: java.time.format.DateTimeParseException: Text '2022-04-21 00:00:00' could not be parsed: Unable to obtain Instant from TemporalAccessor: {HourOfAmPm=0, MicroOfSecond=0, NanoOfSecond=0, MilliOfSecond=0, MinuteOfHour=0, SecondOfMinute=0},ISO resolved to 2022-04-21 of type java.time.format.Parsed

...

Caused by: java.time.DateTimeException: Unable to obtain Instant from TemporalAccessor: {HourOfAmPm=0, MicroOfSecond=0, NanoOfSecond=0, MilliOfSecond=0, MinuteOfHour=0, SecondOfMinute=0},ISO resolved to 2022-04-21 of type java.time.format.Parsed

...

Caused by: java.time.temporal.UnsupportedTemporalTypeException: Unsupported field: InstantSeconds

What comes from my investigation, is that the root cause is the lack of a time zone, but my question is how do I specify the time zone using the annotation only?


Solution

  • See DateTimeFormatter. It should be HH for 24 hours time (0-23) i.o. hh for 12 hours time (1-12). The error is caused by hour "00". Fortunately, otherwise you would have only the first half of the day.

    See h, k, H and K.

    The class Instant does not use units like seconds, is more a long internally. Use LocalDateTime for your format.